I did this with Fools Rush In (Matthew Perry & Salma Hayek) last weekend and One Fine Day (Melanie Griffith & George Clooney) just the other night. I've seen them more than enough times, but watch them every time they're on.
Strange but true - guilty pleasures, "teen" movies I just have to watch:
10 Things I Hate About You (Heath Ledger, Julia Stiles)
She's All That (Freddie Prinze Jr., Rachel Leigh Cook)
Never Been Kissed (Drew Barrymore, David Arquette)
Down To You (Freddie Prinze Jr., Julia Stiles)
Drive Me Crazy (Melissa Joan Hart)
Can't Hardly Wait (Eathan Embry, Jennifer Love Hewitt)